The crisis over the suspected use of chemical weapons in Syria’s civil war intensified as western powers and allies of the Middle Eastern country hardened their opposing stances on a likely response.
Tensions rose as unidentified snipers opened fire on a convoy of UN inspectors investigating whether chemical weapons were used in an attack last Wednesday in a suburb of the Syrian capital Damascus.
US secretary of state John Kerry heaped further pressure on Syrian president Bashar al-Assad saying that his regime's use of chemical weapons was "a moral obscenity" and "undeniable".
Syria and her allies have blamed opponents for the suspected gas attack on a rebel-held eastern suburb of Damascus that is reported to have killed as many as 1,300, including women and children.
'Accountability'
In the strongest signal yet that the Obama administration is preparing military intervention against the Assad regime, Mr Kerry said last week's chemical weapons attack should "shock the conscience of the world".
“Make no mistake: President Obama believes there must be accountability for those who would use the world’s most heinous weapons against the world’s most vulnerable people,” he said.
America’s top diplomat stopped short of saying how or when the US would respond, saying Mr Obama would make “an informed decision” on how to react to the “indiscriminate use of chemical weapons”.
A White House spokesman said Mr Obama was evaluating a "response to the clear use" of chemical weapons, which the president has described as a "red line".
The US has strengthened its military presence in the eastern Mediterranean Sea and is said to have prepared options for limited air strikes on Syria to deter the use of chemical weapons.
Speaking ahead of Mr Kerry’s statement, the Syrian president told a Russian newspaper that accusations his forces had used chemical weapons were an “outrage against common sense”.
He warned the US that military intervention in Syria’s two-year civil war would bring “failure just like in all previous wars they waged, starting with Vietnam and up to the present day”.
The attack on the convoy of the UN inspectors, who have been tasked with confirming that a chemical weapons attack took place rather than assigning blame, did not block their work.
The first vehicle in the UN-marked convoy transporting about a dozen inspectors was disabled after being hit in an attack that Syria state media blamed on opposition rebels.
The UN team resumed their mission, visiting two hospitals and speaking to witnesses and survivors of the alleged gas attack and doctors who treated victims.
Security council
Opponents of the Assad regime rallied in a flurry of diplomatic choreography as the UK and Turkey said military intervention could be taken even if the UN Security Council did not reach complete agreement to take action against Syria.
Russia and China, both members of the council who would veto any resolution seeking action against Mr Assad's regime, reiterated their support for the Syrian leader.
Western powers are weighing whether an international consensus for a military response is required.
British foreign secretary William Hague said it was possible to respond to a chemical weapons attack without the full support of all members of the security council.
“Otherwise it might be impossible to respond to such outrages, such crimes, and I don’t think that’s an acceptable situation,” he said.
